Audi 80/Avant (B4)

since 1991-1995 release

Repair and operation of the car


Audi 80/Avant
+ Technical specification
- Engines
   Basic elements
   Lubrication system
   Ventilation of a case
   Visual check of the engine
   Running in of the new engine
   Engine service life
   Nominal and maximum frequency of rotation
   Restriction of frequency of rotation
   Measurement of pressure of compression
   List of malfunctions
   Provorachivaniye of the engine
   Hydraulic pushers
   Works on the GRM gear belt
   List of malfunctions
   Removal and installation of a head of the block of cylinders
   Removal and installation of the engine
+ System of production of the fulfilled gases
+ Cooling system
+ Fuel tank and fuel pump
+ Air filter and airintaking channels
+ System of injection
+ Coupling
+ Transmission and transmission
+ Suspension bracket and steering
+ Brake system
+ Anti-blocking system of brakes
+ Wheels and tires
+ Body electrical system
+ System of ignition
+ Lighting
+ Signalling devices
+ Devices and auxiliary devices
+ Heating and ventilation
+ body Elements
+ Search of malfunctions
+ Specifications




Hydraulic pushers

For check of hydraulic pushers it is necessary to press a plastic or wooden wedge (1) the unloaded hydraulic pushers (2). Metal tools with which it is possible to scratch easily a surface of a hydraulic pusher, cannot be used.

For what hydraulic pushers are necessary?

Because of heating of the engine components of the drive of valves are extended. Therefore between a camshaft and dish-shaped pushers there has to be a small gap in order that and at the warmed engine valves densely were closed despite the cores which became longer. This gap, a so-called gap in the valvate drive, at old cars it was necessary to regulate through certain periods. At the Audi 80 car similar action automatically happens at each movement of valves thanks to the so-called hydraulic regulation of a gap in valves located in dish-shaped pushers. From here and name "hydraulic pushers". See the description of work in this chapter above.

Knocks of valves

The knocking noise in the field of a head of the block of cylinders (also see above in this chapter) indicate one or several defective hydraulic pushers.

Knock of valves can arise, however, and at a prolnost serviceable hydraulic pushers, if:

  • Supply of pushers with oil is not provided yet – the engine got warm not enough.
  • The car shortly before that worked in full loading at high external temperatures.
  • The car long time did not eskpluatirovatsya. In this case knock of valves has to stop the latest at achievement by the engine of working temperature.
  • At very low level of oil the oil pump sometimes involves air.

Search of a faulty hydraulic pusher

 PERFORMANCE ORDER

  1. To start the engine and to leave to work until the electric fan of the cooling system does not start working for the first time.
  2. To increase rotation frequency approximately to 2500 rpm for two minutes.
  3. If knock of valves does not stop, to stop the engine and to uncover heads of the block of cylinders.
  4. To install the first cylinder on ignition moment VMT.
  5. To press down both dish-shaped pushers near the first cylinder a wooden wedge down. If the pusher moves more than on 0,1 mm, it needs to be replaced (as pushers cannot be repaired).
  6. To repeat this procedure with other cylinders. For this purpose to expose the corresponding cylinder in situation VMT. VMT is exposed in case on the controlled cylinder camshaft cams evenly show up.

Replacement of a hydraulic pusher

 PERFORMANCE ORDER

  1. To remove a camshaft.
  2. To extend an old dish-shaped pusher.
  3. To oil a little directing a pusher and to insert a pusher.
  4. To put a camshaft.
  5. After installation of a new dish-shaped pusher it is impossible to start the engine within 30 min.! He has to "sit down" at first. Otherwise valves can face pistons.